The Chinese word for size is
大小

dàxiǎo

Translations for size and their definitions

尺寸
1. n. size (typically of clothes); dimensions (gl, of an object); measurement; fitting
2. n. standard; yardstick
3. n. sense of propriety; proper limits (of decorum, speech, behaviour, etc.)
4. n. (literary) small amount

大小
1. n. big and small
2. n. size (of dresses, shoes, etc.); proportions; dimensions; magnitude
3. n. old and young; adults and children
4. n. senior and junior; degree of seniority
5. adv. at any rate; anyway
6. adv. (cln, zh, antonymous compounds)